/*
 * @(#)GpsUtils.java
 * 2017年12月29日 下午3:51:31
 * 
 *
 * Copyright (c) 2018-2028, HangZhou QiYun InfoTech Co.,Ltd. .
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.qyxx.platform.inf.gps.core;

/**
 * GPS坐标转换类
 * 
 * @author gxj
 * @version 1.0 2017年12月29日 下午3:51:31
 * @since jdk1.6
 */

public class GpsUtils {

	public static double pi = 3.1415926535897932384626;
	public static double x_pi = 3.14159265358979324 * 3000.0 / 180.0;
	public static double a = 6378245.0;
	public static double ee = 0.00669342162296594323;

	public static double transformLat(double x, double y) {
		double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y
				+ 0.1 * x * y + 0.2 * Math.sqrt(Math.abs(x));
		ret += (20.0 * Math.sin(6.0 * x * pi)
				+ 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
		ret += (20.0 * Math.sin(y * pi)
				+ 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;
		ret += (160.0 * Math.sin(y / 12.0 * pi)
				+ 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;
		return ret;
	}

	public static double transformLon(double x, double y) {
		double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y
				+ 0.1 * Math.sqrt(Math.abs(x));
		ret += (20.0 * Math.sin(6.0 * x * pi)
				+ 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
		ret += (20.0 * Math.sin(x * pi)
				+ 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;
		ret += (150.0 * Math.sin(x / 12.0 * pi)
				+ 300.0 * Math.sin(x / 30.0 * pi)) * 2.0 / 3.0;
		return ret;
	}

	public static double[] transform(double lat, double lon) {
		if (outOfChina(lat, lon)) {
			return new double[] { lat, lon };
		}
		double dLat = transformLat(lon - 105.0, lat - 35.0);
		double dLon = transformLon(lon - 105.0, lat - 35.0);
		double radLat = lat / 180.0 * pi;
		double magic = Math.sin(radLat);
		magic = 1 - ee * magic * magic;
		double sqrtMagic = Math.sqrt(magic);
		dLat = (dLat * 180.0)
				/ ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
		dLon = (dLon * 180.0)
				/ (a / sqrtMagic * Math.cos(radLat) * pi);
		double mgLat = lat + dLat;
		double mgLon = lon + dLon;
		return new double[] { mgLat, mgLon };
	}

	public static boolean outOfChina(double lat, double lon) {
		if (lon < 72.004 || lon > 137.8347)
			return true;
		if (lat < 0.8293 || lat > 55.8271)
			return true;
		return false;
	}

	/**
	 * 84 to 火星坐标系 (GCJ-02) World Geodetic System ==> Mars Geodetic System
	 * 
	 * @param lat
	 * @param lon
	 * @return
	 */
	public static double[] gps84_To_Gcj02(double lat, double lon) {
		if (outOfChina(lat, lon)) {
			return new double[] { lat, lon };
		}
		double dLat = transformLat(lon - 105.0, lat - 35.0);
		double dLon = transformLon(lon - 105.0, lat - 35.0);
		double radLat = lat / 180.0 * pi;
		double magic = Math.sin(radLat);
		magic = 1 - ee * magic * magic;
		double sqrtMagic = Math.sqrt(magic);
		dLat = (dLat * 180.0)
				/ ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
		dLon = (dLon * 180.0)
				/ (a / sqrtMagic * Math.cos(radLat) * pi);
		double mgLat = lat + dLat;
		double mgLon = lon + dLon;
		return new double[] { mgLat, mgLon };
	}

	/**
	 * * 火星坐标系 (GCJ-02) to 84 * * @param lon * @param lat * @return
	 */
	public static double[] gcj02_To_Gps84(double lat, double lon) {
		double[] gps = transform(lat, lon);
		double lontitude = lon * 2 - gps[1];
		double latitude = lat * 2 - gps[0];
		return new double[] { latitude, lontitude };
	}

	/**
	 * 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 将 GCJ-02 坐标转换成 BD-09 坐标
	 * 
	 * @param lat
	 * @param lon
	 */
	public static double[] gcj02_To_Bd09(double lat, double lon) {
		double x = lon, y = lat;
		double z = Math.sqrt(x * x + y * y)
				+ 0.00002 * Math.sin(y * x_pi);
		double theta = Math.atan2(y, x)
				+ 0.000003 * Math.cos(x * x_pi);
		double tempLon = z * Math.cos(theta) + 0.0065;
		double tempLat = z * Math.sin(theta) + 0.006;
		double[] gps = { tempLat, tempLon };
		return gps;
	}

	/**
	 * * 火星坐标系 (GCJ-02) 与百度坐标系 (BD-09) 的转换算法 * * 将 BD-09 坐标转换成GCJ-02 坐标 *
	 * * @param bd_lat * @param bd_lon * @return
	 */
	public static double[] bd09_To_Gcj02(double lat, double lon) {
		double x = lon - 0.0065, y = lat - 0.006;
		double z = Math.sqrt(x * x + y * y)
				- 0.00002 * Math.sin(y * x_pi);
		double theta = Math.atan2(y, x)
				- 0.000003 * Math.cos(x * x_pi);
		double tempLon = z * Math.cos(theta);
		double tempLat = z * Math.sin(theta);
		double[] gps = { tempLat, tempLon };
		return gps;
	}

	/**
	 * 将gps84转为bd09
	 * 
	 * @param lat
	 * @param lon
	 * @return
	 */
	public static double[] gps84_To_bd09(double lat, double lon) {
		double[] gcj02 = gps84_To_Gcj02(lat, lon);
		double[] bd09 = gcj02_To_Bd09(gcj02[0], gcj02[1]);
		return bd09;
	}

	public static double[] bd09_To_gps84(double lat, double lon) {
		double[] gcj02 = bd09_To_Gcj02(lat, lon);
		double[] gps84 = gcj02_To_Gps84(gcj02[0], gcj02[1]);
		// 保留小数点后六位
		gps84[0] = retain6(gps84[0]);
		gps84[1] = retain6(gps84[1]);
		return gps84;
	}

	/**
	 * 保留小数点后六位
	 * 
	 * @param num
	 * @return
	 */
	private static double retain6(double num) {
		String result = String.format("%.6f", num);
		return Double.valueOf(result);
	}

	/**
	 * 
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub

	}

}
